Graham Hemostasis 2012 / Exam 2 / 2nd deck Flashcards Preview

CVPR 330 Blood > Graham Hemostasis 2012 / Exam 2 / 2nd deck > Flashcards

Flashcards in Graham Hemostasis 2012 / Exam 2 / 2nd deck Deck (42):
1

How does fibrinogen change to fibrin ?

The enzyme Thrombin converts fibrinogen into Fibrin Monometer, Fibrinopeptide A&B. Fibrin Monometers then connect to each other and form the fibrin clot.

2

1.) What Lab Test can we run to measure Fibrinogen quantification (see if Fibrinolysis is taking place) ?
2.) What are the normal values?

1.) D Dimer
2.) 200 - 400 mg/dL
Newborns = 150 - 300 mg/dL

3

Preparation of a Sample for Coagulation Testing ?

- Sodium citrate
- Ratio of blood to
anticoagulant 9:1
- Tube must be full
- Should not be the first tube drawn

4

Prothrombin Time (PT)

3 minutes @ 37 degrees

- Measures the amount of clotting factors 7, 10, 5, & 2 in the Extrinsic System.

5

Activated Partial Thromboplastin Time (APTT)

5 min @ 37 degrees

(Plasma) + Activator phospholipid + surface contact + Calcium Chloride = Time it takes to clot

6

APTT Normal Lab Value:

25 - 35 sec

7

PT Normal Lab Values:

- Normal Lab Value: 50 - 150 % of normal activity
- Normal Lab Value: 10-13 sec

8

Thrombin Time

3 min at 37 degrees

Test to diagnose Thrombin Inhibition.
- Normal Lab Value: 10-15 sec

9

What study can you use to determine deficiency vs. inhibitor ?

Mixing Study
- Patient plasma is mixed with an equal amount of normal plasma and the APTT is then repeated.

* If the time corrects = Deficiency
* If the time does not correct = Inhibitor is present; heparin or antibody.

10

Plasminogen

Anticoagulant Protein

11

Plasminogen may be activated to the proteolytic enzyme PLASMIN by a number or agents, name 2 of them?

TPA
Urokinase

12

Plasmin

proteolytic enzyme that digests fibrin

13

Explain the D -Dimer test ?

Antibody-d-dimer + Plasma = Positive if Agglutination occurs.

14

Congenital factor deficiencies that may prolong PT ?

I
II
V
X
VII

15

Aquired factor deficiencies that may prolong PT or APTT ?

- May be single factor deficiency or multiple factor deficiency. that my prolong PT ?

- It could be a production problem.
- or a Consumption problem.

16

Inhibitors that may prolong PT ?

- Heparin (some heparins in some test systems)
- Lupus-like anticoagulant (high dose)
- Paraproteins
- Elevated FSP

17

Congenital factor deficiencies
that may prolong APTT ?

I
II
V
X
VIII
IX
XI
XII

18

Inhibitors that may prolong APTT ?

- Heparin
- Specific factor inhibitor
- Lupus-like anticoagulant
- Paraproteins
- Elevated FSP

19

Patient is
Bleeding,
Mixing study corrects Abnormal APTT.

What Factors are deficient?

I
II
V
X
VII (vWF)
IX

20

Patient is
NOT bleeding,
Mixing study corrects Abnormal APTT.

What Factors are deficient?

XI
XII

21

Patient is
Bleeding,
Mixing study does NOT correct Abnormal APTT.

What's the problem?

INHIBITORS

- Heparin
- Specific factor inhibitor
- Paraproteins
- Elevated FSP

22

Patient is
NOT bleeding,
Mixing study does NOT correct Abnormal APTT.

What's the problem?

LLAC

23

Factors that may prolong the Thrombin Time ?

- Decreased fibrinogen
- Abnormal fibrinogen
- Thrombin Inhibitors
Heparin
Paraproteins
Increased FSP

24

What is the most common congenital bleeding disorder ?

von Willebrand Disease

25

Criteria for diagnosis of LUPUS

- Prolongation of PT / PTT
- Uncorrectable prolongation of the PT / PTT with addition of normal plasma.
- Absence of specific inhibitory activity against any specific coagulation inhibitor

26

Natural Anticoagulants

- Antithrombin
- Protein C & Protein S
- Tissue factor pathway
inhibitor

27

What natural anticoagulant neutralizes serine proteases ?

Antithrombin

28

What natural anticoagulant inhibit Va and VIIIa ?

Protein C & Protein S

29

What natural anticoagulant neutralizes VIIa and Xa ?

Tissue factor pathway inhibitor

30

Thrombotic Complications in CPB

- Consumptive and hemodilutional losses of natural anticoagulants
- Transfusion of hemostatic products can result in excessive thrombin generation
- HIT
- Inherited hypercoagulable states

31

Heparin Induced Thrombocytopenia (HIT)

- 1-5% of pts exposed to unfractionated heparin will develop HIT.
- 30% of those will develop thrombosis
- Patient forms antibodies to the complex of heparin with PF4 found in the alpha granules of platelets

32

Name 5 Inherited Hypercoagulable States?

- Factor V Leiden
- Prothrombin G20210A
- Elevation of vWF, VIII,
fibrinogen
- Deficiency of natural
anticoagulants
- Increased levels of
Lipoprotein (a) inhibits fibrinolysis

33

Disseminated Intravascular Coagulation (DIC) definition ?

Secondary condition that results in the increased generation of thrombin. Making clots leads to fibrinolysis (the breaking down of clots) which leads to a vicious cycle.

34

Disseminated Intravascular Coagulation (DIC) fibrinolytic example ?

Hemorrhagic Purpura Meningococcal Septicemia

35

Disseminated Intravascular Coagulation (DIC) Thrombotic example ?

Gangrene Haemophilus B Septicemia

36

Thrombin Removes fibrinopeptides A and B, forming fibrin monomers which
results in ?

Decreased Fibrinogen

37

Thrombin Activates V, VIII, and XIII. As it is formed, it consumes what ?

factor II

38

Thrombin also Stimulates platelets, which leads to what ?

thrombocytopenia

39

Activation of Fibrinolysis leads to 4 things, what are they?

- Increased plasmin generation
- Lysis of clots
- Consumption of fibrinogen
- Increased levels of FSP and
D-Dimer

40

Laboratory Results in DIC

↑ PT, PTT, TT
↑ Fibrin Split Products
↓ Fibrinogen
↓ Platelets
- Schistocytes on peripheral
smear

41

6 Conditions Associated with DIC?

- Infections
- Obstetric complications
- Surgery, including CPB
- Malignancies
- Massive tissue injury
- Snakebite

42

Anticoagulant Therapy

* Thrombin Inhibitors
- Heparin
- Direct thrombin inhibitors
* Warfarin compounds
(Coumadin)
* Antiplatelet therapy